Caliper - Vernier Scale and Other Types of Calipers
A caliper or a pair of calipers is a measurement tool used to measure the distance between two opposite sides of an object. Calipers usage is wide: from medicine, science, mechanical engineering, woodworking metalworking to forestry.
In ancient Greece, people used calipers some two thousand and six hundred years ago. The oldest calipers are the one that was found near the Italian island Giglio on the ship from the sixth century BC. Those calipers were wooden. Greeks and also Romans were using calipers. Another caliper is found in China, dating from 9 AD during the Chinese Xin Dynasty. Joseph R. Brown invented the modern caliper. That caliper was invented in 1851 and could read to thousandths of an inch. It was also a cheap tool so that ordinary machinists could afford it.
Types of Calipers
There are a few types of calipers. The most popular are:
- Vernier Caliper
- Inside Caliper
- Outside Caliper
- Divider Caliper
- Dial Caliper
- Digital Caliper
- Oddleg Caliper
- Micrometer Caliper
An inside caliper is a measurement tool used for measuring the internal size of an object. It can be adjusted manually with the screw.
Unlike inside calipers, there is outside calipers, which measure an object's external size. This tool can give a high level of accuracy. It works similarly to the inside caliper with and without the screws. This kind of caliper is usually made from high-carbon steel.
Another type of caliper is a divider caliper or a compass, a popular name. A divider caliper is used for marking out locations.
Oddleg caliper is a type of caliper used to draw a line a set distance from the edge of a workpiece.
Vernier Scale
Vernier scale is a measuring instrument that can measure with huge precision. Scientists, machinists, and surveys use the Vernier scale in navigation. The other name for a vernier scale is a nonius, commonly used in English by the eighteenth century.
One of the primary usages of the vernier scale is the measurement of an object's external diameters, internal diameters, and depth. When measuring with the vernier scale, the user first must read the fixed scale and then the finer scale for the most accurate measuring result. It can show the measuring results with an accuracy of up to two decimals.
One of the main reasons why vernier scales work so well is that most people can detect which lines are aligned and which are not. This ability can even improve with practice. The name of his ability is vernier acuity; because of it, the vernier scale has an advantage compared to other measuring devices.
Other Types of Calipers
A dial caliper is a type of caliper with a simple dial instead of a vernier mechanism. That dial reads the final fraction of a millimeter or inch. The dial rotates once per every inch or millimeter.
Digital caliper is also a type of caliper with a digital display that gives information about the precise measuring result by showing the numbers on it.
One caliper that uses a screw for measurement rather than a slide is called a micrometer.
